参数资料
型号: ST72621J2T1
厂商: STMICROELECTRONICS
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDSO20
封装: 0.300 INCH, PLASTIC, SO-20
文件页数: 97/136页
文件大小: 2475K
代理商: ST72621J2T1
ST7262
63/136
SERIAL PERIPHERAL INTERFACE (Cont’d)
10.4.8 Register Description
CONTROL REGISTER (SPICR)
Read/Write
Reset Value: 0000 xxxx (0xh)
Bit 7 = SPIE Serial Peripheral Interrupt Enable.
This bit is set and cleared by software.
0: Interrupt is inhibited
1: An SPI interrupt is generated whenever
SPIF=1, MODF=1 or OVR=1 in the SPICSR
register
Bit 6 = SPE Serial Peripheral Output Enable.
This bit is set and cleared by software. It is also
cleared by hardware when, in master mode, SS=0
(see
(MODF)). The SPE bit is cleared by reset, so the
SPI peripheral is not initially connected to the ex-
ternal pins.
0: I/O pins free for general purpose I/O
1: SPI I/O pin alternate functions enabled
Bit 5 = SPR2 Divider Enable.
This bit is set and cleared by software and is
cleared by reset. It is used with the SPR[1:0] bits to
set the baud rate. Refer to Table 18 SPI Master
0: Divider by 2 enabled
1: Divider by 2 disabled
Note: This bit has no effect in slave mode.
Bit 4 = MSTR Master Mode.
This bit is set and cleared by software. It is also
cleared by hardware when, in master mode, SS=0
(see
0: Slave mode
1: Master mode. The function of the SCK pin
changes from an input to an output and the func-
tions of the MISO and MOSI pins are reversed.
Bit 3 = CPOL Clock Polarity.
This bit is set and cleared by software. This bit de-
termines the idle state of the serial Clock. The
CPOL bit affects both the master and slave
modes.
0: SCK pin has a low level idle state
1: SCK pin has a high level idle state
Note: If CPOL is changed at the communication
byte boundaries, the SPI must be disabled by re-
setting the SPE bit.
Bit 2 = CPHA Clock Phase.
This bit is set and cleared by software.
0: The first clock transition is the first data capture
edge.
1: The second clock transition is the first capture
edge.
Note: The slave must have the same CPOL and
CPHA settings as the master.
Bits 1:0 = SPR[1:0] Serial Clock Frequency.
These bits are set and cleared by software. Used
with the SPR2 bit, they select the baud rate of the
SPI serial clock SCK output by the SPI in master
mode.
Note: These 2 bits have no effect in slave mode.
Table 18. SPI Master mode SCK Frequency
70
SPIE
SPE
SPR2
MSTR
CPOL
CPHA
SPR1
SPR0
SPR2
SPR1
SPR0
Serial Clock
(fCPU = 8MHz)
Serial Clock
(fCPU= 4MHz)
SCK
100
fCPU/4
fCPU/2
2 MHz
000
fCPU/8
fCPU/4
1 MHz
001
fCPU/16
fCPU/8
0.5 MHz
110
fCPU/32
fCPU/16
0.25 MHz
010
fCPU/64
fCPU/32
125 kHz
011
fCPU/128
fCPU/64
62.5 kHz
相关PDF资料
PDF描述
ST72P621L4M1 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDSO34
ST72623F2M1L 8-BIT, MROM, 4 MHz, MICROCONTROLLER, PDSO34
ST7263BK1B/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP32
ST72652AR4T1/XXX 8-BIT, MROM, MICROCONTROLLER, PQFP64
ST72651AR6T1E/XXX 8-BIT, MROM, MICROCONTROLLER, PQFP64
相关代理商/技术参数
参数描述
ST7263-EMU2 功能描述:仿真器/模拟器 ST7 Emulator Board RoHS:否 制造商:Blackhawk 产品:System Trace Emulators 工具用于评估:C6000, C5000, C2000, OMAP, DAVINCI, SITARA, TMS470, TMS570, ARM 7/9, ARM Cortex A8/R4/M3 用于:XDS560v2
ST7265X-EVAL/MS 制造商:STMicroelectronics 功能描述:ST6 EVAL BD - Bulk
ST7265X-EVAL/PFD 制造商:STMicroelectronics 功能描述:USB FLASH EVAL - Bulk
ST7266 制造商:6940 功能描述:ST7266
ST7267C8T1L 制造商:STMicroelectronics 功能描述: